DESCRIPTION (Applicant's abstract): Social phobia is a very prevalent and debilitating disorder with public speaking anxiety being the most common tear among socially phobic individuals. Although there are a number of effective psychosocial treatments for social phobia (e.g., cognitive-behavioral treatments and exposure therapy) very little is known about the underlying mechanism of therapeutic change (i.e., the mediators of change), and the variables that are predictive. of treatment outcome (i.e., the moderators of change). Furthermore; it is unclear why treating individuals for their public speaking anxiety can generalize to other untreated social fears. The primary goal of the present study is to identify the mediators and moderators of change in the treatment of social phobia, and, in so doing suggest a common mechanism of action for all brief psychosocial interventions. Perceived self-efficacy of social behavior, negative cognitive appraisal (estimated social costs), and perceived emotional control will be considered as potential mediators; avoidant personality disorder and the generalized subtype of social phobia will be considered as potential predictors for poor treatment outcome. Individuals meetings criteria for social phobia with significant fear of public speaking will be randomly assigned to either a comprehensive cognitive-behavioral treatment for social phobia (n=43), a performance-based exposure treatment for public speaking anxiety without cognitive intervention (n=43), or a waitlist control group (n=43). Clinician ratings, behavioral tests, cognitive assessments, subjective ratings, and physiological measures will be employed to determine the degree of therapeutic gains in various social phobia domains. The main hypothesis is that perceived emotional control will mediate treatment outcome and generality of effectiveness independent of the specific treatment condition.